 Dimilin - controls the anchor worm parasite (Lernea) and fish lice (argulus) in water gardens, koi ponds and display tanks containing fish, including goldfish, koi and ornamental tropical fish.
Anchor worms are external copepod parasites that infest koi, goldfish and tropical fish. They are not true worms and are classified as crustaceans because their outer body is made of chitin, the same material found in crab shells.
The female anchor worm has a long body up to 25 mm long (1 inch) with anchor-like appendages at the head.
The female attaches to the fish by burrowing through the skin (males die after mating). The anchor becomes firmly embedded into the skin, muscle and organs of the fish. The adult female looks worm-like with two sacs (egg cases) that form an upside down "Y" hanging from the fish.
Will not effect biological filter. | 
